Measles: photos, symptoms, treatment, measles prevention
- Causes of measles
- Mechanism of measles development
- Classification of measles
- Symptoms of measles
- Complications and possible consequences of measles
- Diagnosis of measles
- Treatment of measles
- Prevention of measles
Measles (morbilli) - highly contagious acute viral infection, manifested by high (febrile) temperature, specific exanthema, symptoms of general intoxication, generalized inflammatory lesions of the mucous pharynx, conjunctiva and respiratory organs.
The index of contagiosity in measles is almost 100%, i.е. The risk of infection in a non-vaccinated person in contact with a patient is extremely high. The disease remains one of the main causes of deaths among young children around the world.
Causes of measles
The causative agent of the disease is the RNA virus, belonging to the genus Morbillivinis (family Paramyxoviridae). It is characterized by poor stability in environmental conditions: it is inactivated when exposed to ultraviolet radiation, sunlight, drying, disinfection treatment. Heating to 50 ° C also has a detrimental effect on the virus. At room temperature, it remains viable for a maximum of 1 or 2 days, but often no longer than 4 hours. To maintain activity for several weeks, he needs a lower temperature - the optimal temperature range from -15 to -20 0 С. Despite the low stability in the environment, cases of spreading strains over a long distance through the ventilation system in a separately standing building are known.
The source and reservoir of viruses is a sick person. They spread by airborne droplets. A large amount is excreted with mucus when coughing, sneezing or just talking, starting from the last 2 days of the latency period, throughout the prodromal period, and lasting up to 4 days of rashes. The patient is not dangerous to others from the 5th day from the appearance of a patchy-papular rash. Sometimes the period of contagiosity lasts up to 10 days from the beginning of the formation of exanthema. Cases of asymptomatic carriage of the infection have not been identified.
More often, measles are affected by children under 5 years old. Adults who do not undergo compulsory vaccination are less likely to get sick, but the risk of infection is very high, and the disease is more severe than in children. In the spring-winter period, the peak incidence is observed, and the decline occurs in August and September. After recovery, persistent lifelong immunity persists with the preservation of anti-measurable antibodies in the blood. In newborns whose mothers have had measles, there is a colostral (maternal) immunity, which lasts up to 3 months of the baby's life. Therefore, infection of measles in these months is unlikely. Known single cases of intrauterine infection of the fetus from the mother, who contracted measles during gestation.
Mechanism of measles development
The introduction of viruses into the body occurs through the epithelium of the respiratory tract, the villi of which swell, there are areas of metaplasia and necrosis of the mucosa, vasoconstriction is detected. In the submucosal layer, focal lymphohystocyte infiltration is formed. Then the viruses penetrate into the blood - the primary viremia, and then with its current reach the elements of the reticuloendothelial system, in which they accumulate. In the spleen, lymph nodes, etc., at that time, cells called "Warthin-Finkeldey" are found. They have giant sizes and lots of cores.
After growth, reproduction and vital activity in the lymph nodes viruses re-enter the bloodstream - secondary viremia, affecting all types of leukocytes. At this time, the person has the first clinical signs of the disease.
Measles viruses, affecting T-lymphocytes, suppress both cellular and humoral immune responses. As a result, immunity decreases, the body becomes susceptible to different pathogenic and conditionally pathogenic microflora, which results in the development of serious secondary complications in the form of respiratory infections and a violation of vitamin metabolism with a sharp decrease in retinol and ascorbic acid.
The causative agent is predisposed to integumentary tissues - conjunctiva, skin, oral mucosa, integumentary epithelium of respiratory organs. It is very rare to diagnose measles encephalitis, in which viruses affect the brain.
Classification of measles
- Mitigated and others.
Periods of development of the disease:
- Incubation (latent);
- Catarrhal stage;
- The stage of rashes.
- Period of convalescence.
Forms of measles, differing in severity of the course:
- Light form;
- Of medium gravity;
- Severe form.
Symptoms of measles
The duration of the incubation period varies within 1-2 weeks, sometimes reaches 17 days. In cases of the introduction of a specific immunoglobulin is extended to 3 weeks. The cyclicity of a typical measles form is divided into several periods: catarrhal, the period of rashes and convalescence (convalescence).
The catarrhal (prodromal) period proceeds acutely. The body temperature reaches 38.8-40 0 C and is accompanied by chills. There are manifestations of general intoxication - severe pain in the head, severe weakness, weakness, sleep disturbance, lack of appetite, irritability, etc. Symptoms of intoxication in adults are more pronounced, children are smoothened.
The first sign of the disease is a severe runny nose, accompanied by abundant serous or serous-purulent secretions. Catarrhal lesions of the mucosa of different parts of the pharynx are manifested by a dry "barking" cough, hoarseness, sometimes stenosis of the larynx. At the same time, inflammation of the conjunctiva of the eyes ( conjunctivitis ) with hyperemia and pronounced edema of the eyelids. Because of the purulent discharge from the eyes, the patient often hardly sticks the eyelids in the morning. There is burning and itching in the eyes, watery eyes, photophobia.
In children, symptoms of catarrhal inflammation predominate. When examining the pharynx, the granularity of the posterior wall and the marked hyperemia of the throat are noted. The face is puffy. Against the background of the reddening conjunctive, hemorrhages (hemorrhages) are seen in the retina of the eye. In adults, the signs of regional lymphadenitis and respiratory tract damage come first. Lymph nodes, often cervical, are enlarged and painful on palpation. With auscultation of the lungs, breathing is hard, dry rales are audible. In some cases, the manifestations of dyspepsia disorder - nausea, loose stools, belching or heartburn, are added to the above symptoms.
Approximately on days 2 or 3, the first wave of fever subsides, the temperature decreases and the patient feels relief, but the next day it again sharply increases, exacerbating intoxication and catarrhal phenomena. On the mucous cheeks in the region of molars (rarely on the gums and lips) there are spots of Velsky-Filatov-Koplik, which are small whitish formations, similar to the grains of manga, with a red border around the perimeter. They are a pathogenic sign of measles.
Simultaneously with specific spots or before their appearance on the mucosa of the soft and part of the hard palate, a measly enanthem is formed - specks of red color, each of which does not exceed the size of the head of the pin. Merge after 1 or 2 days from the moment of appearance, they cease to be noticeable against the background of general reddening.
The catarrhal stage lasts for children no longer than 3-5 days, in adults - not more than a week.
The period of rashes replaces catarrhal. A measles rash on the skin is a characteristic sign of this period. It initially appears behind the ears and on the scalp in the area of hair growth, extending to the face, neck area and chest. On the second day, the skin of the shoulders, arms, back, belly is covered with a rash, on the third - the lower extremities, including the fingers, and on the face pales. This sequence of rash propagation, characteristic of measles, is an important criterion for differential diagnosis.
Spotted-papular exanthema is more pronounced in adults than in children. Has a tendency to discharge and acquire a hemorrhagic character in the severe course of the disease.
The period of rashes is considered to be the height of measles. Against the background of the appearance of skin rash fever becomes the most pronounced, the symptoms of intoxication are exacerbated, the catarrhal symptomatology is amplified. When the patient is examined, arterial hypotension, tachycardia , signs of bronchitis and / or tracheobronchitis are found.
The period of convalescence or pigmentation occurs approximately 8-10 days after the onset of the disease, in adults a few days later. Body temperature is normalized, signs of catarrhal inflammation gradually disappear. Skin rashes regress in the order in which they appear. In their place remain the pigmented areas, completely disappearing in 5-7 days, but with leaving after itself a temporary otrubrious peeling, especially on the face. The patient feels well.
This period often develops an asthenic syndrome, manifested by the symptoms of neurological disorders - a decrease in muscle tone and skin reflexes, tremor of the head and / or hands. There are episodes of seizures. These phenomena are transitory.
Mitigated measles is one of the atypical clinical forms of infection. Such a variant of measles is diagnosed in people who previously had this infection or passed passive or active immunization. Essential differences from the typical form:
- Longer incubation;
- Shortened period of catarrhal phenomena;
- Absence of rashes of Velsky-Filatov-Koplik;
- Complete absence or minimal signs of intoxication;
- Small amount of elements of the rash;
- An atypical sequence of rashes: an exanthematous rash may appear either immediately on the skin of the entire body, or in the reverse order - on the ascending from the lower extremities to the face.
Abortive measles is another variant of the atypical form of the disease. The beginning is similar to a typical measles, but the symptomatology subsides for 2-3 days. The febrile temperature lasts on the first day of rashes. The rash is localized only on the skin of the face and trunk.
At a hypertoxic measles the intoxication is sharply expressed. The hemorrhagic variant of atypical measles is manifested by hematuria, multiple hemorrhage into the mucous membranes and skin, a stool with an admixture of blood.
Complications and possible consequences of measles
Various consequences arise from the weakening of the immune system, which makes the viral infection complicated by the attached bacterial infection. In patients with measles, secondary bacterial pneumonia is often diagnosed. Rare, but possible stomatitis.
Other characteristic complications from the respiratory organs:
- Angina ;
- Pleurisy ;
- Bronchitis ;
- Laryngitis ;
- Stenosis of the larynx.
On the part of the digestive system:
- Enterocolitis with bowel dysfunction;
- Measles hepatitis.
From the side of the lymphatic system:
- Mesenteric lymphadenitis .
The greatest danger is the defeat of the nervous system. Infection can lead to the development of meningoencephalitis or meningitis, as well as polyneuritis. Inflammatory lesion of the brain - encephalitis - in children can be accompanied by cramps, hyperkinesis, progressive visual impairment, paralysis.
Diagnosis of measles
With the typical form of measles, the diagnosis is easy to establish, based on a characteristic clinical picture and epidemiological data.
- Clinical blood test . For a virus infection, a decrease in the number of leukocytes (leukopenia) and lymphocytes (lymphopenia) per unit volume of blood is characteristic. With complication of bacterial character, an increase in the number of leukocytes (leukocytosis), neutrophilic granulocytes (neutrophilia) and ESR is revealed.
- Immunological method - RPGA (direct haemagglutination reaction) - is necessary for detection of anticorrosive antibodies.
- Agglutination inhibition reaction (RTGA) is a specific diagnostic test that allows to confirm the diagnosis, depending on the growth of titres of measles antibodies.
- Serologic examination for detection of antibodies to the virus itself or its components.
- Immunoenzyme analysis (ELISA) is an immunological test that helps detect antibodies to the virus. In an acute process, an increase in specific IgM immunoglobulins is detected, in the presence of a chronic or previously transmitted infection, the presence of an IgG antibody.
- Immunofluorescence (MFA) methods are immunofluorescence studies using various methods for the quantitative and qualitative determination of antibodies and antigens.
Bacteriological analysis of flushing from the nasopharynx and serological studies in clinical practice are rarely used, since their results are retrospective.
Depending on the complications, additional instrumental studies are prescribed. If pneumonia is suspected, X-rays of the lungs are necessary, with meningitis - lumbar puncture, brain damage - electroencephalography or rheoencephalography of the brain.
Treatment of measles
In most cases, measles is treated as an outpatient. Hospitalization in the infectious department is required in case of severe illness with complications. Compliance with bed rest is necessary throughout the fever period and the next two days after the temperature normalization.
Specific etiotropic therapy has not been developed to date. Treatment is symptomatic, aimed at stopping manifestations of the disease and preventing the development of complications. Intoxication in the mild course of the disease is removed with a plentiful drink. In a hospital, detoxification therapy is carried out with intravenous administration of saline and polarizing solutions.
To lower the temperature, antipyretic and non-steroidal anti-inflammatory drugs are used. To remove itching and irritation, antihistamines help. Vitamins are necessary to fill their deficits. Taking antiviral drugs from the first days of the disease significantly improve its course. If the threat of joining a bacterial infection or already started pneumonia, laryngitis, bronchitis or other inflammation of the respiratory tract necessarily prescribed a course of antibiotics a wide range of activities. Catarrhal manifestations are removed by mucolytics and anti-inflammatory aerosols. With conjunctivitis, eye drops are added to the treatment.
The patient should observe the hygiene of the eyes, mouth and whole body. Eyes wash with furatsilinom, strong tea or weak solution of baking soda, and the pharynx and the entire oral cavity with chlorhexidine or other antiseptic. With inflammation of the larynx, accompanied by stenosis, or measles encephalitis, large doses of corticosteroids are required.
Prevention of measles
The most reliable prevention of measles is a routine vaccination with live measles vaccine, conducted in accordance with the developed vaccination calendar, to create active immunity against measles viruses. According to the plan, the first combined vaccination against three infectious diseases - mumps, measles and rubella - is performed by one-year-olds when the passive (innate) immunity transmitted through the placenta from the mother ceases to function.
It is allowed to administer associated vaccines against these infections on the same day as vaccination against diphtheria, poliomyelitis, tetanus, hepatitis B, chicken pox, etc. The question of simultaneous vaccination is decided by a pediatrician for each child individually, based on his state of health.
The next inoculation (revaccination) is done to children at the age of 6 before starting school. Adolescents under 17 years of age, and adults up to 35 years of age who have not been vaccinated and who have not been previously ill, are also given a measles vaccine. Under the instruction it is necessary to make two inoculations, the interval between which should not be less than 3 months. People in the epidemic outbreak and previously uninoculated are shown mandatory vaccination regardless of their age.